The present invention relates to an integrated system and method for managing heat rejection from not only a vehicle's prime mover and electronic componentry.
The management of heat rejection from various vehicular systems, subsystems, and components has been the subject of much engineering effort since the dawn of the automotive age. Following earlier attempts at direct air cooling of prime movers, air-to-liquid heat exchangers became the dominant mechanism for rejecting waste heat from powertrains, whether based on conventional internal combustion engine technology, or hybrid technology, or other types of powertrains. Air-to-liquid heat exchangers are the preferred means for rejecting waste heat from vehicular heating, ventilating, and air conditioning (“HVAC”) systems, as well.
There are at least two drawbacks to conventional automotive air-to-liquid heat exchange systems. In general, vehicular air conditioning condensers are usually located within a stream of “new”, or unheated, ambient air. Having flowed through the HVAC condenser, the cooling air then flows serially through additional heat exchangers, such as a prime mover heat exchanger and/or an electronics heat exchanger. While promoting efficient operation of the HVAC system, a disadvantage of this arrangement resides in the fact that the heated air flowing from the HVAC condenser has a reduced capacity to absorb heat, thereby limiting the system's ability to transfer heat from coolant flowing through the downstream heat exchangers. Moreover, although it may be acceptable to mount additional heat exchangers on the roof of a vehicle, such as is commonly done with commercial vehicles, the additional fact is that, with passenger vehicles, the ability to mount a heat exchanger so as to access a flow of ambient temperature air is circumscribed by the dictates of styling and packaging. The present system and method provide a means for achieving acceptable cooling with a single air stream flowing serially through a number of heat exchangers, by controlling the addition of heat to the air stream.